This invention relates generally to an apparatus for dispensing a surfactant, such as foam, over an area and, in particular, it relates to a new and improved apparatus for dispensing foam to extinguish fires. The apparatus is particularly suitable for installation on heavy mobile equipment, such as tractors, bulldozers and other similar equipment used in fighting fires, particularly forest fires.
It has been determined that in fighting wildfires, such as forest fires or even chemical fires in a more confined area, foam is about eighty-six percent (86%) more effective than water alone. That is, water is about eight percent (8%) effective in fire fighting while foam is about ninety-four percent (94%) effective in extinguishing wildfires. While water is still needed to extinguish fires even where foam is the dominant element being used, it has been determined that the amount of water needed is reduced by approximately seventy-five percent (75%) when used in combination with foam than where the water is used alone. The combination of foam and water expands the volume or the capacity of the foam by approximately seven (7) to ten (10) times the normal volume of a foam used alone.
Despite the remarkable advantage of foam in fighting wildfires, there is a problem which exists in the prior art devices used to dispense the foam and the problem usually occurs after the foam and water have been mixed. Thus, once the foam and water have been combined, which is a necessary step when foam is used, there is still a problem of getting the high quality of foam, i.e., bubbles, needed for dispensation over a desired area which would be effective in fighting wildfires. The problem is magnified when the water and foam mixture is allowed to sit as a combination for a period after the two elements have been mixed and are unused for a period of time, during which the foam starts to substantially lose its forming ability or ability to make bubbles which are needed to extinguish the fires. This problem can result even where the foam and water mixture is allowed to sit for minutes, not hours. Thus, even though the water is needed to facilitate the foaming activities of the foam surfactant, the combination or mixture of the foam and water, if allowed to stand for a period of time results in a foam being dispensed which is not much more effective than water alone to fight wildfires.
The above-described problem becomes even more acute when human life is at stake such as the life of the firefighter who is operating the heavy equipment for dispensing the foam or other surfactant. With very large wildfires advancing with a velocity of between 35-45 miles per hour for a period of two (2) to three (3) minutes, it is imperative that the person operating the equipment for dispensing the substance for fighting the fire, is at least himself protected from the swift oncoming flames. The problem described above is one which is to applicant's knowledge well known in the art and is prevalent in most, if not all existing, surfactant dispensing apparatuses and is one to which a solution is urgently needed. It is therefore desirable to have an apparatus which is capable of dispensing a high quality of usable foam for a period of 3-4 minutes over a desired area to combat the flames which are rapidly advancing at a very high velocity, to not only extinguish the wildfire but, more importantly, to protect the life of the firefighter. Such an apparatus does not exist today.
The prior art apparatuses are either unable to respond in the time period required (0-3 minutes) or are unable to dispense the quality of foam or other surfactant needed or both.